缓释氮肥配施尿素对冬小麦产量和氮肥利用效率的影响OA

A two-factor randomized block design was conducted in the 2022-2023 and 2023-2024 seasons.Factor A comprised two nitrogen fertilizer types:urea(U)and slow-release fertilizer-urea 7∶3(CU).Factor B comprised five nitrogen application rates:0 kg·hm-2(N0,no nitrogen application control),75 kg·hm-2(N75),150 kg·hm-2(N150),225 kg·hm-2(N225),and 300 kg·hm-2(N300,traditional N application rate).A total of nine treatments were established to systematically analyze the effects of slow-release fertilizer-urea combination application under reduced nitrogen fertilizer rates on winter wheat growth and development,dry matter accumula-tion,yield,and nitrogen uptake and utilization.This study aims to provide a theoretical basis for optimizing nitrogen fertilizer application technology in arid farming areas of Northwest China.The results showed that,based on the traditional N application rate of 300 kg·hm-2 and the conventional N application mode(single application of u-rea),the moderate N reduction to 225 kg·hm-2 and the combination of slow-release fertilizer-urea fertilization strategy were conducive to promoting the growth and development of winter wheat,and at the same time,signifi-cantly improved its yield and nitrogen absorption and utilization efficiency.Compared with the N300-U treatment,the N225-CU treatment increased leaf area index,nitrogen accumulation at maturity,yield and economic benefits of maize by 2.49％to 19.25％,12.55％to 20.22％,10.26％to 11.50％and 16.82％to 19.10％,respectively.Compared with the single-applied urea N225-U,the combined treatment N225-CU showed higher performance in terms of spikes per hectare,number of grains in spikes,and 1000-grain weight,with the yield increased by 9.13％to 9.21％.The N225-CU treatment significantly enhanced nitrogen fertilizer use efficiency in winter wheat.Com-pared to the N225-U treatment,its nitrogen fertilizer partial productivity,nitrogen agronomic efficiency,and nitro-gen recovery efficiency increased by 19.27％,20.41％,and 28.82％on average,respectively.In summary,for ni-trogen fertilizer management in rain-fed winter wheat,moderately reducing nitrogen fertilizer application to 225 kg·hm-2 while adopting a 7∶3 slow-release fertilizer-urea application ratio holds significant importance for achieving nitrogen reduction and yield increase in winter wheat within semi-humid and semi-arid regions.